As of now, PVE gear is still being scaled down to 496 in arena and only Grievous 522 gear is retaining its ilvl. The PVE gear ilvl cap in arena's will gradually go up weekly until it matches the 522 ilvl of the PVP gear.

I think the way they designed the new PVE trinkets makes them slightly less attractive scaled down, so players wouldn't want to use them in pvp. Personally as human/engi I still like Relic(484)/pvp on-proc str for damage until I replace them with a Grievous trinket, but i'm going back and forth with relic and the on-use strength. I'm just not a fan of the on-use as ret, I prefer the double proc trinkets.

Edit: Now that the conquest vendors are back up. I'm really liking grievous proc / relic for damage.